Can I reverse the PdV integral for work?

AI Thread Summary
The discussion revolves around whether the work integral W = ∫PdV can be reversed to W = ∫V dP, given specific parameters of a thermodynamic problem. The user has values for pressures and volume but lacks total mass, final volume, and temperatures. They propose solving for volume as a function of pressure and integrating, but seek confirmation on the validity of this approach. The response indicates that reversing the integral is not straightforward and suggests using integration by parts instead. The conclusion emphasizes the need for careful consideration of the integration process in thermodynamic equations.
Hercuflea
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Homework Statement


I have a problem where I know P1, P2, V1, and molecular mass. I do not know total mass, final volume, temperature 1 or temperature 2, or the work. I also know that P = 40V^2 + 20

Can I reverse the W = ∫PdV equation into the form W = ∫V dP? Because I could just solve the equation for V = sqrt(P/40 - 1/2) and integrate that. Can I do this?


Homework Equations


W = ∫PdV


The Attempt at a Solution



Qdot - Wdot = mdot ((u2 + v^2/2 + gz2) - (u1 + v^2/2 +gz1))
no heat transfer, constant mass, no change in altitude, no velocity. The system is being compressed.
 
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Hercuflea said:
Can I reverse the W = ∫PdV equation into the form W = ∫V dP? .
Not quite. Integration by parts: ##\int_a^by.dx + \int_{y(a)}^{y(b)}x.dy = [xy]_{x=a}^{x=b}##
 
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